Since b and d are perpendicular the angles they form are 90 degree angles. Also given that a and b are parallel the angles between a and d are the same as those with b and d.
So 25%=1/4 so technically you just do 5 times 4 since you need 4 more to have a full 4/4 or full 100% so 5 times 4 is 20 so there are 20 totals toys in the bag